The effect of heart rate and vessel angulation on coronary artery stenosis evaluation from cardiac CT angiography

Abstract

Introduction Cardiac CT angiography (CCTA) is considered a valuable tool for non-invasive assessment of coronary artery stenoses in patients with low to intermediate risk for coronary artery disease. Purpose To investigate the effect of heart rate and artery orientation on the accuracy of stenosis quantification from CCTA studies. Materials and methods A QRM CT cardiac phantom equipped with cardiac motion simulator was subjected to standard prospective and retrospective CCTA image acquisitions on a modern 128-slice CT scanner. CCTA image series were separately produced for three coronary artery phantoms representing stenosis of 25%, 50% and 75% with heart rate varying from 40 to 120 bpm (in 10 bpm steps) and vessel orientation varying from 0° to 40° (in 10° steps) with respect to z-axis. Stenoses were evaluated by an experienced radiologist using a dedicated cardiac CT software for coronary artery assessment and analysis. Results Stenosis quantification accuracy was found to be considerably deteriorated for increasing heart rate (p Conclusion High inaccuracies in coronary artery may occur for increased heart rate during the CCTA scan acquisition with the effect being more prominent for increased vessel angulations. To suppress stenosis evaluation inaccuracy below 15%, beam heart rate during the examination should be maintained